CN108059134A - A kind of method that hydrogen hot plasma method prepares high-purity nm aluminium nitride - Google Patents
A kind of method that hydrogen hot plasma method prepares high-purity nm aluminium nitride Download PDFInfo
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- CN108059134A CN108059134A CN201711289231.9A CN201711289231A CN108059134A CN 108059134 A CN108059134 A CN 108059134A CN 201711289231 A CN201711289231 A CN 201711289231A CN 108059134 A CN108059134 A CN 108059134A
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- nitrogen
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/06—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron
- C01B21/072—Binary compounds of nitrogen with metals, with silicon, or with boron, or with carbon, i.e. nitrides; Compounds of nitrogen with more than one metal, silicon or boron with aluminium
- C01B21/0722—Preparation by direct nitridation of aluminium
- C01B21/0724—Preparation by direct nitridation of aluminium using a plasma
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
Abstract
The invention discloses a kind of methods that hydrogen hot plasma method prepares high-purity nm aluminium nitride, start plasma generator by DC power supply；Using nitrogen and hydrogen as the discharge gas importing plasma generator so that nitrogen and hydrogen generate electric arc electric discharge in the plasma generator, the high-temperature plasma jet stream based on nitrogen and hydrogen is formed；The high-temperature plasma jet stream is imported into straight tubular reactor, the high purity aluminum powder of vaporization with being blown into from the multiple air admission holes being arranged symmetrically in opposite directions being arranged on the straight tubular reactor using carrier gas nitrogen is had an effect, so that discharge gas high temperature nitrogen is reacted with the high purity aluminum powder vaporized, so as to obtain aluminium nitride powder.The method of the present invention has the advantages that yield is high, product purity is high and size tunable.
Description
Technical field
The invention belongs to inorganic non-metallic material preparation fields, and in particular to a kind of hydrogen hot plasma method prepares high-purity receive
The method of rice aluminium nitride.
Background technology
Aluminium nitride (AlN) is a kind of covalent crystal with hexagonal wurtzite structure, lattice constant a=0.3110nm, c=
0.4978nm.Al atoms form [A1N4] tetrahedron of distortion with adjacent N atoms, are along c-axis direction Al-N bond distance
0.1917nm, in addition the Al-N bond distance in 3 directions is 0.1885nm, and the theoretical density of AlN is 3.26g/cm3.Aluminium nitride is comprehensive
The new advanced ceramics material of function admirable is closed, having excellent high heat conductance, (theoretical thermal conductivity is 319Wm-1·K-1), it is reliable
Electrical insulating property, low dielectric constant and dielectric loss, it is nontoxic and match with silicon linear expansion coefficient (293~773K, 4.8
×10-6) etc. a series of good characteristics, it is considered to be highly intergrated semiconductor substrate of new generation and the preferable material of electron device package
Material, receives the extensive attention of domestic and international researcher.In addition, it also has high intensity, high rigidity (12GPa), high bending strength
The good physical property such as (300~400MPa) and excellent chemical stability and corrosion resistance.Even if in high temperature, still have
Preferable high temperature and chemical stability, temperature is 1000 DEG C in air and when temperature reaches 1400 DEG C in a vacuum can still protect
It is fixed to keep steady, thus as a kind of inorganic material with wide application prospect.AIN has many excellent performances, its application
Field is very wide, except being used for processing or making electronic package material, piezoelectric device, structural ceramics, coating, heater, fire proofed wood
Material, electro-optical device etc., AIN can also be widely used in the development in composite material.
There are many AlN powder synthetic methods, mainly there is 4 kinds at present, respectively aluminium powder direct nitridation method, Al2O3Carbon thermal reduction
Method, chemical vapour deposition technique (CVD) and self- propagating method.Aluminium powder direct nitridation method is passed through nitrogen at high temperature using aluminium powder as raw material,
AIN powders are directly synthesized, reaction temperature is generally 800-1200 DEG C, but since nitridation reaction is strong exothermic reaction, reacts
Process is difficult to control, unstable product quality, and AlN powder obtained is often from sintering phenomenon, and the AlN layers of aluminium powder nitrided surface
The progress of reaction can be hindered, it is necessary to which high-purity AlN can be made in high pure raw material, and corresponding cost also improves, and it is straight to constrain aluminium powder
Connect the popularization of nitriding；Al2O3Carbothermic method needs high reaction temperature, and needs second of decarbonizing technology, manufacturing cost
It is high；The obtained purity of chemical vapour deposition technique (CVD) is very high, but byproduct of reaction is comparable to equipment corrosion serious, and raw material
It is of high cost；The shortcomings of self- propagating method is again low there are product purity, and reaction process is difficult to control.
The content of the invention
The present invention for conventional method prepares series of problems existing for aluminium nitride, provide it is a kind of it is brand-new, technique is simple
Single, aluminium nitride size tunable can obtain the preparation method of high-purity nitrogen aluminium powder without post-processing purification.
The invention discloses a kind of methods that hydrogen hot plasma method prepares high-purity nm aluminium nitride, are made by DC power supply
Plasma generator starts；Nitrogen and hydrogen are imported into the plasma generator so that nitrogen and hydrogen as discharge gas
Gas generates electric arc electric discharge in the plasma generator, forms the high-temperature plasma jet stream based on nitrogen and hydrogen；
The high-temperature plasma jet stream is imported into straight tubular reactor, it is and multiple opposite on the straight tubular reactor from being arranged on
The high purity aluminum powder for the vaporization that the air admission hole being arranged symmetrically is blown into using carrier gas nitrogen is had an effect so that the high temperature in discharge gas
Nitrogen is reacted with the high purity aluminum powder vaporized, so as to obtain aluminium nitride powder.
Further, by changing described in the flow of the nitrogen and hydrogen and the output power of the DC power supply
The temperature range of plasma jet is 6000-15000K, wherein, the total flow scope of the nitrogen and hydrogen is 1-100m3,
The volume ratio of nitrogen and hydrogen is 1:1-1:3, the output power range of the DC power supply is 10-1000kW.
Further, the plasma reactor is the water-cooling jacket cast reaction for making liner by heat safe graphite
Device, the suitable for reading of the plasma reactor are used to import the plasma jet, the inside of the plasma reactor
Wall offers 1 to 8 air admission hole being arranged symmetrically in opposite directions to import the high purity aluminum powder of the vaporization, the 30- under the air admission hole
Stomata is also set up at 50mm to be passed through ammonia in reaction.
Further, the purity of the high purity aluminum powder is more than 99%, and grain size is 300-500 mesh.
Further, the aluminium nitride is protected with pickling.
Further, the aluminium nitride is further purified with deionized water.
The advantageous effect that the present invention reaches：Aluminum nitride powder yield can reach more than 70%, and the purity of product is reachable
More than 99%, average grain diameter is about between 300-400 mesh, it is clear that, grain higher than the product purity that Conventional processing methods obtain
Footpath is controllable.Aluminum nitride powder prepared by this method can be applied to electronic package material, piezoelectric device, structural ceramics, coating, heating
Device, refractory material, electro-optical device, it is also possible to prepare composite material.When aluminum nitride powder does composite material, smaller powder
Body grain size is conducive to scattered in composite material.Therefore, superfine aluminium nitride powder, which has, preferably applies potential quality.
Description of the drawings
The feature of exemplary embodiment of the present, advantage and technique effect described below with reference to the accompanying drawings.
Fig. 1 prepares superfine aluminium nitride powder flow path figure for hydrogen heat plasma method of the present invention；
Fig. 2 is the structure chart of reactor of the present invention.
In the accompanying drawings,
1：Plasma generator； 2：DC power supply； 3：Powder collecting tank；
4：Straight tubular reactor； 5：Nitrogen cylinder； 6：Hydrogen cylinder；
7：Aluminium powder storage tank； 8：Heating unit； 9：Spinner flowmeter；
10：Tail gas absorption groove； 11：Plasma generator cathode；
12：The plasma generator first anode； 13：Plasma generator second plate.
Specific embodiment
Embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples.Following embodiment it is detailed
Thin description and attached drawing cannot be used for limiting the scope of the invention for illustratively illustrating the principle of the present invention, i.e., of the invention
Described preferred embodiment is not limited to, the scope of the present invention is defined by the claims.
For implementing the process system of the technological process of the present invention as shown in Figure 1.Process system include DC power supply 2,
Plasma generator 1, straight tubular reactor 4, powder collecting tank 3 and raw material feed system composition.Plasma generator 1 by
Cerium tungsten and copper product respectively constitute plasma generator cathode 11 and plasma generator anode, and plasma generator anode includes
The first anode 12 and second plate 13.Nitrogen cylinder 5 and hydrogen cylinder 6 are anti-by respective spinner flowmeter 9 and plasma respectively
Device 1 is answered to connect, so as to the supply of nitrogen gas and hydrogen into plasma reactor 1.Plasma generator 1 is in DC power supply 2
Driving under can generate nitrogen hydrogen high-temperature plasma jet stream.Straight tubular reactor is made of water-cooling jacket liner graphite-pipe, and
It is connected by flange with plasma generator 1；Heat exchanger tube uses single tube cooling jacket, and goes out with plasma reactor 1
Mouth connection；Gas-solid separator uses screen mesh type filter core, and is connected with heat transfer tube outlet end；Feed system includes aluminium powder storage tank 7, aluminium
Powder heating unit 8 and spinner flowmeter 9, aluminium powder heating unit 8 is for vaporizing the aluminium powder in aluminium powder storage tank 7, spinner flowmeter 9
For controlling the flow for the vaporization aluminium powder being transported in plasma reactor 1 so that the aluminium powder being passed through from reactor top steams
Vapour and high-temperature plasma jet mixing.In reactor under hydrogen plasma effect, pass through following reaction：
2Al+2N2→2AlN
Superfine aluminium nitride powder is obtained in powder collecting tank 3, powder collecting tank 3 uses decanter type principle.It is ultra-fine to what is received
Aluminum nitride powder can also further be purified with deionized water, can remove impurity.
As shown in Fig. 2, plasma reactor 1 is the water-cooling jacket tube-type reactor for making liner by heat safe graphite,
The suitable for reading of plasma reactor is used to import plasma jet；1-8 holes are offered on the madial wall of plasma reactor
To import aluminium powder gas；The lower mouth of plasma reactor is used to make the gas outflow after reaction, high temperature nitrogen and aluminium powder gas
It is mixed in reactor, and is rapidly completed reaction.High temperature nitrogen is discharge gas, by nitrogen cylinder and aluminium powder tank bottom air inlet
It is connected, the charging rate for connecting to control aluminium powder by the stream for controlling nitrogen, carrier gas nitrogen flow is controlled by spinner flowmeter 9
System, generally sets 0.5-1m3/h.In addition, also setting up a stomata at 30-50mm under air admission hole, ammonia is passed through in reaction.
As shown in Figure 1, start DC power supply 2 and plasma generator 1, first with to from nitrogen cylinder 5 via rotor stream
Gauge 9 export argon gas discharging with plasma generator 1 into line replacement clean, be then gradually added into discharge gas from
Hydrogen cylinder 6 is via the hydrogen that spinner flowmeter 9 exports to required flow.Plasma jet temperature range is 6000-15000K,
Can be by changing the output power of nitrogen and hydrogen flowing quantity and plasma electrical source, the range of flow of nitrogen and argon gas is
1-100m3, the output power range of plasma electrical source is 10-1000kW.After device stabilization, from straight tubular reactor 4
Portion is passed through the vaporization aluminium powder for the regulation flow sent out from aluminium powder storage tank 7 with carrier gas nitrogen via spinner flowmeter 9 and comes from
The high-temperature plasma jet mixing of plasma generator 1.Make height under hydrogen gas plasma effect in straight tubular reactor 4
Warm nitrogen reacts with vaporization aluminium powder.
The aluminum nitride powder obtained from powder collecting tank 3 weigh with scale divided by react consumption raw material in aluminium powder quality,
Obtain reaction yield.It the results are shown in Table 1.
In order to analyze gained aluminum nitride powder purity, product is sent to the progress of Institute of Analysis of national non-ferrous metal research institute
Elemental analysis.Acquired results are as shown in table 2.Wherein, the elements such as Mg, Al, Ca, Ti, Cr, Fe, Ni, Zn, Si are by inductively etc.
Gas ions mass spectrum (ICP-MS) provides；Cu elements are provided by inductively coupled plasma atomic radiation spectrum (ICP-AES), C element
It is analyzed by high-frequency melting infrared detecting method, O, N element is detected by pulsed infrared thermal conductivity method, and B element is obtained by Subtraction method.
The elemental analysis result of 2 aluminum nitride powder of table
In addition, the size of obtained aluminum nitride powder is measured.Aluminum nitride powder sample is put into ethyl alcohol with ultrasound first
Wavelength-division dissipates, and then carries out SEM observations.By picture, it can be seen that, the diameter of most of particles is in 50-200nm scopes.
The content that described in the invention and explanation embodiment is protected for the present invention is illustrative rather than restricted
, it is therefore to be understood that being, the preferred embodiment of the present invention only has shown and described in above-described embodiment, is limited in claims
In the range of all modifications example and equivalent arrangements belong to the content protected of the present invention.
Claims (6)
1. a kind of method that hydrogen hot plasma method prepares high-purity nm aluminium nitride, it is characterised in that：
Start plasma generator by DC power supply；
The plasma generator is imported so that nitrogen and hydrogen are in the plasma using nitrogen and hydrogen as discharge gas
Electric arc electric discharge is generated in generator, forms the high-temperature plasma jet stream based on nitrogen and hydrogen；
The high-temperature plasma jet stream is imported into straight tubular reactor, it is and multiple on the straight tubular reactor from being arranged on
The high purity aluminum powder for the vaporization that the air admission hole being arranged symmetrically in opposite directions is blown into using carrier gas nitrogen is had an effect so that high temperature nitrogen and vapour
The high purity aluminum powder of change is reacted, so as to obtain aluminium nitride powder.
2. the method as described in claim 1, it is characterised in that：Pass through the flow for changing the nitrogen and hydrogen and the direct current
The temperature range of plasma jet described in the output power of power supply is 6000-15000K, wherein, the nitrogen and hydrogen
Total flow scope be 1-100m3, the volume ratio of nitrogen and hydrogen is 1:1-1:3, the output power range of the DC power supply
For 10-1000kW.
3. the method as described in claim 1, it is characterised in that：The plasma reactor is by heat safe graphite work
The water-cooling jacket tube-type reactor of lining, the suitable for reading of the plasma reactor is used to import the plasma jet, described
The madial wall of plasma reactor offers 1 to 8 air admission hole being arranged symmetrically in opposite directions to import the rafifinal of the vaporization
Powder also sets up stomata to be passed through ammonia in reaction under the air admission hole at 30-50mm.
4. the method as described in claim 1, it is characterised in that：The purity of the high purity aluminum powder is more than 99%, grain size 300-
500 mesh.
5. the method as described in claim 1, it is characterised in that：The aluminium nitride is protected with pickling.
6. the method as described in claim 1, which is characterized in that further purified to the aluminium nitride with deionized water.
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| CN201711289231.9A CN108059134A (en) | 2017-12-07 | 2017-12-07 | A kind of method that hydrogen hot plasma method prepares high-purity nm aluminium nitride |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022073351A1 (en) * | 2020-10-10 | 2022-04-14 | 浙江宇耀新材料有限公司 | Aluminum nitride nanopowder synthesis production line |
| CN115025735A (en) * | 2022-05-11 | 2022-09-09 | 四川轻化工大学 | Preparation method and device for synthesizing AlN powder based on laminar plasma beam |
| CN115028459A (en) * | 2022-07-22 | 2022-09-09 | 成都物熙科技有限公司 | Method and device for preparing high-purity superfine aluminum nitride powder body by using plasma |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2022073351A1 (en) * | 2020-10-10 | 2022-04-14 | 浙江宇耀新材料有限公司 | Aluminum nitride nanopowder synthesis production line |
| CN115025735A (en) * | 2022-05-11 | 2022-09-09 | 四川轻化工大学 | Preparation method and device for synthesizing AlN powder based on laminar plasma beam |
| CN115028459A (en) * | 2022-07-22 | 2022-09-09 | 成都物熙科技有限公司 | Method and device for preparing high-purity superfine aluminum nitride powder body by using plasma |
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Application publication date: 20180522 |